Broaching tool



Oct. 7, 1969 J ANDRs ET AL 3,470,729

BROACHING TOOL Filed Sept. 22. 1966 INVENTORS: JERRY F ANDRS KERMIT ELLEDGE ATTORNEY United States Patent Office 3,470,729 Patented Oct. 7, 1969 3,470,720 BROACHING TOOL Jerry Frank Andrs, Chester, and Kermit Elledge, Prince George, Va., assignors to Allied Chemical Corporation, New York, N.Y., a corporation of New York Filed Sept. 22, 1966, Ser. No. 581,310 Int. Cl. B23d 43/00; B21c 25/10; B23p 15/42 U.S. Cl. 72--476 3 Claims ABSTRACT OF THE DISCLOSURE A breaching tool having a first sphere-shape breaching element on the working end thereof and a distance therefrom a second sphere-shaped breaching element having a diameter greater than the first breaching element for smoothing spinnerette capillaries.

The present invention relates to a breaching tool and more particularly to a breaching tool for smoothing spinneret capillaries after drilling and reaming.

As is known in the manufacture of spinnerets, it is usually common to drill a series of orifices in a spinneret plate and the drilled orifices are thereafter reamed and then breached to smooth out the interior of the orifices. These orifices are known in the art as spinneret capillaries. The breaching operation is necessary because it is very difficult to drill orifices in spinneret plates which are considered a finished product requiring no further treatment. Conventional apparatus normally employed for the breaching operation generally takes the form of a shaft-like tool which is rounded at the end which enters the spinneret capillary. Unfortunately, conventional breaching tools are difiicult to insert and to remove from the spinneret capillary. :In addition, it is difficult to Work the tool through the capillary of the spinneret.

An object of the present invention is to provide a breaching tool to smooth spinneret capillaries after drilling and reaming, which breaching tool is easy to insert and withdraw from the spinneret capillary to be serviced. Another object is to provide a breaching tool which permits the breaching to be done in increments thereby requiring less working energy to service the material than heretofore possible.

These and other objects are accomplished by the present invention wherein there is provided a breaching tool which comprises a rod having a working end portion and a holding end portion, said working end portion having less cross-sectional area than said holding end portion and having disposed thereon .a plurality of breaching elements, said breaching elements nearest to said holding end portion being sized progressively larger than the breaching elements further away from said holding end portion.

For a clearer understanding of the invention, reference is made to the drawing which is a view in perspective showing the breaching tool of the present invention. It will be seen that the breaching tool comprises a rod having a working end portion 11 and a holding end portion 12. The holding end portion is adapted to be inserted into an apparatus capable of securing and rotating the rod, such as a drill and the like. The rod is preferably formulated from a metal and is preferably solid throughout its entire length.

As will be seen from the drawing, the holding end portion 12 is of a larger cross-sectional area than the working end portion 11, the latter being sized to permit the entrance of the working end portion into the material to be serviced i.e., into the orifice or capillary of the spinneret to be breached. Disposed near one end of the working end portion 11 of the rod 10 preferably at the extreme end, is a breaching element 13 which is showr in the drawing as being in the form of a solid sphere or knob having a larger cross-sectional area than the working end portion 11 and is of a size and configuration such as to be capable of breaching the capillary 01 a spinneret when it is forced through the capillary. Positioned next to the knob 13 and approximately one capillary length therefrom is another knob 14 which is slightly larger in dimension than the knob 13. Thus, knob 13 is sized to perform the first increment of breaching ol the orifice in the spinneret, whereas the second knot 14 is positioned and sized to add the last and final in crement of breaching. It will be obvious that by spacing the knobs at least one capillary length apart that no additional force would be required to push the rod througl the first spinneret orifice. Although only two such breach ing elements are shown, it will be obvious that more thar two can be employed, each being sized progressively larger as they approach the holding end portion.

In a representative technique of operation, the material to be serviced, for example, the spinneret plate Which has been drilled and reamed through its widtl to form the capillary orifices are positioned in a manner such as to permit the breaching tool to pass througl' the orifices of the spinneret plate. For this purpose, the same drilling apparatus used to drill the capillaries ir the spinneret plate can be employed with the breaching tool being inserted in the place which normally accommodates the drill. Under the conditions of operation, the rod approaches the spinneret plate and the working end portion enters the capillary to be serviced. The first knol: positioned on the rod engages the spinneret capillary and passes therethrough until the second knob positioned about one capillary length away reaches the opening of the capillary. The same downward force causes the seconc knob to pass through the capillary opening thereby completing the breaching operation.

By employing the apparatus of the present invention the breaching operation becomes relatively simple since the breaching tool is easy to insert and withdraw from the capillary. Moreover, the breaching is done in increments thereby requiring less working energy to service the material than heretofore possible.

Although certain preferred embodiments of the invention have been disclosed for purpose of illustration, it will be evident that various changes and modification: may be made therein without departing from the scope and spirit of the invention.

We claim:

1. A breaching tool for breaching spinnerette capillaries which comprises a rod having a working-end portion and a holding-end portion, said working-end pertior having lesser cross-sectional area. than said holding-end portion and having rigidly secured thereon a first sphereshaped breaching element disposed on the extreme end of said working-end portion and forming a terminal part thereof and a second sphere-shaped element spaced and secured a capillary length therefrom and having a diameter greater than said first element.

2. A breaching tool as described in claim 1 further characterized by at least one additional sphere-shaped breaching element spaced a capillary length from saic second element and having a diameter progressively larger than the first and second sphere-shaped elements.

3. A breaching tool as described in claim 2 in which the sphere-shaped elements are selectively spaced whereby not more than one of said elements are within a :apillary simultaneously.

References Cited UNITED STATES PATENTS Bunting 2995.1 Hook 2995.1 Wakefield et al. 2995.1 McCarty 72479 X Hart 29--95.1 10

5 CHARLES W. LANHAM, Primary Examiner E. SUTTON, Assistant Examiner US. Cl. X.R. 72479 

